Colorectal cancer (CRC) is a highly preventable cancer, yet it is a leading cause of cancer death in the US. Disparities in CRC morbidity and mortality by socio-economic position and race/ethnicity have been documented. While individual health behaviors do not fully explain differentials in mortality by socioeconomic position, they are significant determinants of societal patterns of risk. These patterns reflect the social context, or larger structural forces that shape the texture of people's day-to-day realities, and that include an array of social and material resources that ultimately have profound effects on health. Little research has been conducted to date to examine how best to intervene within a social context, or to determine what settings are best for addressing contextual factors. Low-income housing sites have great potential as a channel for addressing disparities, as many social contextual factors occur in the housing setting. The goal of this project is to evaluate an intervention designed to address colorectal cancer prevention (CRC) through low income housing sites. A key aspect of the intervention is to determine ways in which addressing the social context in low income, ethnically diverse populations may address disparities in CRC prevention. This study is a randomized controlled trial that will be conducted in 10 diverse low income housing sites; eligible residents will be enrolled in a cohort and followed; housing site will be the unit of randomization and intervention. The intervention conditions are: (1) a social contextual, housing site-based intervention, that addresses individual, organizational, and systems-level factors that influence participation in CRC prevention activities; or (2) minimal treatment control. The primary outcomes are physical activity and participation in colorectal cancer screening. Of note, both interventions will offer equivalent access to CRC screening. A key goal of this project is to determine if adding on-site outreach and contextually focused activities yield greater overall changes in the study outcomes and is more cost-effective, compared to self-help materials plus efforts to reduce barriers to screening access.